• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.4
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• pp.502-508
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• 2009

Antimicrobial activity of Sargassum thunbergii was determined by paper disc assay and minimum concentration inhibitor (MIC) test. A water extract of S. thunbergii did not show the antimicrobial activity, but an ethanol extract of S. thunbergii (SHE) inhibited Serratia liquefaciens, Salmonella Typhimurium, Pseudomonas aerogenosa and all of the tested gram-positive bacteria at 4 mg/mL. Especially, Bacillus subtilis, Clostridium perfringens and Listeria monocytogenes were susceptible to SHE. As the results of MIC test, SHE inhibited the growth of B. subtilis, Staphylococcus aureus and Listeria monocytogenes at concentration of $0.1{\sim}0.3%$, and inhibited C. perfringens at 0.01%. In the thermal and pH stability test for SHE, antibacterial activities of SHE were maintained when the SHE was treated at $121^{\circ}C$ for 15 minutes or under pH $2{\sim}8$. SHE was partitioned in the order of n-hexane, chloroform, ethyl acetate and butanol. As the results of the MIC test for each obtained fraction, no fraction exhibited higher antibacterial activity than that of the crude SHE. However, a mixture of chloroform, ethylacetate and ethanol fractions showed higher antibacterial activity than SHE.

• Korean Journal of Veterinary Research
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• v.36 no.4
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• pp.795-807
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• 1996

This study was conducted to identify the effects of caffeine on the lipid and protein components or blood chemistry levels of the serum as well as the total homogenate, mitochondrial and microsomal fraction of the rat(Sprague-Dawley, female) liver. Acute test were conducted to determine those effects. The acute test was conducted by dividing rats into 7 groups according to the time lapsed after a single oral administration of 100mg/kg caffeine(that is control, 2hrs, 4hrs, 8hrs, 24hrs, 48hrs and 72hrs lapsed group). The concentrations of glucose, urea nitrogen, uric acid, creatinine, total protein, albumin, A/G ratio, triglyceride, total cholesterol, HDL-cholesterol, free fatty acid, phospholipid as well as the activities of alanine aminotransferase(ALT), aspartate aminotransferase(AST) and alkaline phosphatase(ALP) were measured in the serum of each experimental groups. The concentrations of the carbonyl group, malondialdehyde(MDA) and the patterns of the SDS-PAGE(Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis) were analyzed to determine the oxidative damages and metabolic changes on the lipid and protein components in the serum, and total homogenate, mitochondrial and microsomal fractions of the rat liver. The results obtained from this study were summarized as follows; 1. The concentrations of serum glucose were significantly higher(p<0.01) between 4(143.0mg/dl) and 8hrs(138.0mg/dl) in comparison to that of the control(101.1mg/dl) after a single oral administration of caffeine(100mg/kg). While on the other, there were no significant differences in the concentrations of urea nitrogen, uric acid, creatinine, total protein, albumin and albumin/globulin(A/G) ratio in comparison to those of the control. 2. The concentrations of total cholesterol and HDL-cholesterol in serum were significantly higher(p<0.01) between 4(77.4mg/dl, total cholesterol) and 8hrs(64.7mg/dl, HDL-cholesterol) in comparison to those of the control(62.8, 46.7mg/dl) after a single oral administration of caffeine(100mg/kg). On the other hand, the concentrations of triglyceride in serum were significantly lower(p<0.01) after 8hrs(38.8mg/dl) in comparison to that of the control(66.5mg/dl). 3. The activities of AST in serum was significantly higher(p<0.05) from 2hrs(149U/L) to 8hrs(178U/L) in comparison to the control(112U/L) after a single oral administration of caffeine(100mg/kg). The activities of ALT in serum were significantly higher(p<0.01) at 4(45.5U/L), 24(49.3U/L), 48(46.8U/L) and 72 hrs(42.3U/L) in comparison to that of the control(39.7U/L) after a single oral administration of caffeine(100mg/kg). On the other hand, there were no significant differences in the activities of ALP in comparison to that of the control. 4. The concentrations of free fatty acid in serum were significantly higher(p<0.01) at 8hrs(65.0mg/dl) in comparison to that of the control(37.6mg/dl) after a single oral administration of caffeine(100mg/kg). However, there were no significant differences in the concentrations of carbonyl group and malondialdehyde within serum, and liver homogenate, mitochondrial and microsomal fractions in comparison to that of the control. 5. The patterns of SDS-PAGE in serum, mitochondrial and microsomal fraction of the liver showed no significant differences.

• Journal of Life Science
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• v.32 no.2
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• pp.135-141
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• 2022

Thymosin β-4 (TB4) is a small peptide composed of 43 amino acids. To obtain sufficient biologically active mouse TB4 economically, we cloned and overexpressed this gene in an Escherichia coli system. With the isopropyl β-D-1-thiogalactopyranoside induction of the E. coli transformant, TB4 fusion protein with intein- and chitin-binding domain was successfully expressed in the soluble fraction within the E. coli cell. The TB4-intein - chitin-binding domain fusion protein was purified from the soluble fraction of E. coli cell lysate. The affinity chromatography with chitin beads and dithiothreitol-mediated intein self-cleavage reaction releases the TB4 peptide into the stripping solution. Sodium dodecyl sulphate - polyacrylamide gel electrophoresis and Western blot analyses were used to confirm that the recombinant TB4 peptide was produced with the expected size of 5 kDa. We found that the recombinant TB4 stimulated cell migration in the transwell plate chamber assay. After 18 hr of the treatment of the recombinant TB4 with 1 ng/ml concentration, the migration of the HT1080 cell was increased by 20% compared with that of the chemically synthesized TB4. The recombinant TB4 was also observed to promote the healing of a wound area in C57BL/6 mice by as high as 35% compared with that of the chemically synthesized TB4. These results suggest that the recombinant TB4 has better biological activity for cell migration and wound healing than that of the chemically synthesized TB4 peptide.

• Journal of Life Science
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• v.20 no.2
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• pp.260-268
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• 2010

The lactate dehydrogenase (EC 1.1.1.27, LDH) isozymes in tissues from Channa argus were purified and characterized by biochemical, immunochemical and kinetic methods. The activity of LDH in skeletal muscle was the highest at 380.4 units and those in heart, eye and brain tissues were 13.4, 3,5 and 5.4 units, respectively. Citrate synthase (EC 4.1.3.7, CS) activity in heart tissue was the highest at 20.7 units. LDH/CS in skeletal muscle, heart, eye and brain tissues were 172.9, 0.6, 0.32 and 0.47. Protein concentration in skeletal muscle tissue was 14.7 mg/g and specific activities of LDH in skeletal muscle, heart, eye and brain tissues were 25.88, 0.79, 0.31 and 1.38 units/mg, respectively. Therefore, skeletal muscle tissue was anaerobic and heart tissue was aerobic. The LDH isozymes in tissues were identified by polyacrylamide gel electrophoresis, immunoprecipitation and Western blot with antiserum against $A_4$, $B_4$, and eye-specific $C_4$. LDH $A_4$, $A_3B$, $A_2B_2$. $AB_3$ and $B_4$ isozymes were detected in every tissue, $C_4$, $AC_3$, $A_2C_2$ and $A_3C$ were detected in eye tissue, and $A_3C$ was found in brain tissue. LDH $A_4$, $A_3B$, $A_2B_2$, $AB_3$, $B_4$, eye-specific $C_4$ isozymes were purified by affinity chromatography and Preparative PAGE Cells. The LDH $A_4$ isozyme was purified in the fraction from elution with $NAD^+$ containing buffer of affinity chromatography. Eye-specific $C_4$ isozyme was eluted right after $A_4$, after which $B_4$ isozyme was eluted with plain buffer. As a result, one part of molecular structures in $A_4$, $B_4$ and eye-specific $C_4$ were similar, but were different from each other in $B_4$ and $C_4$. Therefore the subunit A may be conservative in evolution, and the evolution of subunit B seems to be faster than that of subunit A. The activity of LDH $A_4$, $A_2B_2$, $B_4$, and eye-specific $C_4$ isozymes remained at 39.98, 21.28, 19.67 and 16.87% as a result of the inhibition by 10 mM of pyruvate, so the degree of inhibition was very high. The $Km^{PYR}$ values were 0.17, 0.27 and 0.133 mM in $A_4$, $B_4$ and eye-specific $C_4$ isozymes, respectively. The optimum pH of LDH $A_4$, $B_4$, eye-specific $C_4$, $A_2B_2$, $A_3B$, and $AB_3$ were pH 6.5, pH 8.5, pH 5.5, pH 6.0-6.5, pH 5.0 and pH 7.5. The $A_4$ and heterotetramer isozymes stabilized a broad range of pH. Especially, LDH activities in skeletal muscle tissue were high, resulting in a high degree of muscle activity.LDH metabolism in eye tissue seems to be converted faster from pyruvate to lactate by eye-specific $C_4$ isozyme as eye-specific $C_4$ have the highest affinity for pyruvate, and right after the conversion, oxidation of lactate was induced by $A_4$ isozyme. It was found that expression of Ldh-C, affinity to substrate and reaction time of $C_4$ isozyme were different according to the ecological environmental and feeding capturing patterns.

• Journal of Nutrition and Health
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• v.36 no.1
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• pp.9-17
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• 2003

The preparation method of a soluble dietary fiber from oak wood (Quercus mongolica) and the effect of the soluble dietary fiber on physiological function in rat fed high cholesterol diets was investigated. The best condition for steam explosion method was 25 kgf/㎤ pressure for 6 min. The exploded samples were delignified by the filtration treatment with 1% NaOH for several times, which is the best condition. The enzymatic hydrolysis of Cellusoft cellulase was more effective than Onozuka R-10 cellulase. The manufactured soluble dietary fiber was assayed using gel permeation chromatography (GPC) and it was dissolved in water. Average molecular weight distribution of manufactured soluble dietary fiber was about 348-1,200 and it was assumed the oligomer form fraction. In order to compare the manufactured soluble dietary fiber with commercial soluble dietary fiber (pectin) on the physiological function, Sprague-Dawley male rats weighing 100$\pm$10 g were randomly assigned to one normal diet and five high cholesterol diet containing 1% cholesterol. The high cholesterol diet groups were classified to fiber free diet (FF group), 5% pectin (5P group), 10% pectin (l0P group), 5% manufactured soluble dietary fiber (5M group) and 10% manufactured soluble dietary fiber (10M group). Body weight gains in all soluble dietary fiber groups were lower than FF group. Food intakes were increased in all soluble dietary fiber groups than that of FF group. Food efficiency ratio (FER) was significantly decreased in all soluble dietary fiber groups than that of the FF group, and it was especially was highest in 10% supplemented soluble dietary fiber group. The weight of liver of the soluble dietary fiber supplemented groups were lower than those of the FF group, but weights of cecum and small intestine of all supplemented soluble dietary fiber groups were significantly increased, compared with that of FF group. The weights and water contents in feces were significantly increased by the soluble dietary fiber. The activity of the glutamic oxaloacetic transaminase in soluble dietary fiber groups were significantly decreased than those of FF group. The hepatic glutathione S-transferase activity in all soluble dietary fiber supplemented groups were higher than that of FF group. The physiological effects of the manufactured soluble dietary fiber are the same as the commercial soluble dietary fiber (pectin). The preparation method of the soluble dietary fiber from the oak chips suited to its purpose. (Korean J Nutrition 36(1) : 9~17, 2003)

• Journal of Korean Society of Forest Science
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• v.45 no.1
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• pp.62-67
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• 1979

Ultraviolet microscopy of ultrathin sections of wood has proved to be one of the useful means for determining the lignin distribution in the various regions of the cell wall. Also, spectral approach and quantitative analysis of isolated compound middle lamella fraction from birch xylem have revealed that the lignin associated with the vessel secondary wall and middle lamella is composed predominantly of gualacylpropane units. Lignin deposited in the fiber and ray parenchyma secondary walls is composed mostly of syringylpropane units. The middle lamella lignin around fibers and ray cells contains both guaiacyl and syringyl propane quits. On the basis of the results above, this research was carried out to clarify the origin of milled wood lignin (MWL) by analysing the chemical characteristics of ML MWLs extracted at various milling stages. The amount of phenolic hydroxyl-, ${\alpha}$-carbonyl-, and methoxyl-group in the MWL's increases the milling time. And progressive mining contributes to the merease of ratio of syringylaldehyde to vanillin(S/V ratio) after nitrobenzene oxidation of MWL. Accordingly, It could be concluded that milled wood lignin extracted at the initial milling stage derives from compound middle lamella region of cell wall, whereas, with progressive milling, lignin of secondary wall of fiber is introduced gradually to milled wood lignin. These results are suggesting that heterogeneous chemical structure of lignins in hardwood exists. Although milled wood lignin at the initial stage seems to have lower molecular weight in comparison with milled wood lignin extracted at final milling stage from the result of Gel-filtration curves, further study would be required on molecular weight distribution of milled wood lignin in future.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.670-678
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• 1994

The effects of amylase addition during extrusion cooking of rice on the physico-chemical properties of the extrudates were investigated in order to develop rice-based Korean style weaning food products. A laboratory-built single screw extruder was used, the enzymes used were Termamyl 120LS(amylase from Bacillus licheniformis, NOVO Co.), BAN 240L(amylase from Bacillus amylolichuefaciens, NOVO Co.) and malt powder. By the addition of enzymes, the water soluble index of the extrudates increased by 3 times compared to that of the extrudates without enzyme and the concentration of reducing sugar in the extrudates increased drastically at 28 feed moisture. The gel permeation chromatographic pattern showed that the large molecular starch fractions diminished by the addition of enzyme during extrusion and the low molecular fraction increased. The residual enzyme activity in the extrudate were 27% for the most thermo-resistance enzyme by treating at $140^{\circ}C$ in the metering section of the extruder. The sediment volume of the extrudate dispersion increased as the metering section temperature increased to $140^{\circ}C$ . By the addition of enzymes the viscosity of extrudate dispersion was redused $1/4{\sim}1/200$ of that of the extrudates without enzyme. It allowed to use 1.8 times of solid material to the weaning food formulation to attain the same level of consistency as the commercial products. It proves that the addition of amylase during rice extrusion is effective to increase the energy density of weaning food by starch degradation, which results in the increases of water solubility, reducing sugar content, dispersibility and fluidability.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.1
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• pp.60-66
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• 1986

The muscles of wild and cultured eel, Anguilla japonica, were analyzed for the protein composition and amino acid profile. The differences of the subunit distribution for the sarcoplasmic and myofibrillar proteins were discussed with sodium dodecylsulfate(SDS) polyacryamide gel electrophoresis. The muscle protein in wild eel was composed of $30.78\%$ of sarcoplasmic, $59.02\%$ of myofibrillar, $9.73\%$ of residual intracellular and $2.47\%$ of stroma fraction. That in cultured eel was composed of $31.81\%,\;58.37\%,\;8.16\%\;and\;1.80%$, respectively, The sarcoplasmic and myofibrillar proteins were composed of 16 and 14 subunits in wild eel, and 22 and 15 subunts in cured eel. The sarcoplasmic protein between wild and cultured muscles showed a similar trend in the subunits, except a few subunits such as 36,500, 46,000, 58,500, 75,000, 170,000 and 235,000 daltons in cultured eel. Only the existence of 45,000 dalton subunit was the difference between wild and cultured eel in myofibrillar protein. The distribution patterns of total amino acid in muscles of wild and cultured eel were found to be very similar trend, although glycine content in wild eel was slightly higher than that in cultured one.

• Korean Journal of Food Science and Technology
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• v.40 no.5
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• pp.522-527
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• 2008

Low molecular peptides were isolated from Asterias amurensis via SDS-PAGE. The peptides were separated via consecutive gel filtration as five fractions (F1-F5) according to molecular weights, based on the results of MALDI-TOF MS analysis. The molecular weight of the most active peptide was estimated as 15,000 daltons. The peptide showed cytotoxicity on normal human fibroblast cells at levels as low as 20% when 1.0 mg/mL of the samples was added. The peptide also exhibited higher levels of nitric oxide production from macrophages than the lipopolysaccaharides. It was determined that prostaglendin $E_2$ production was significantly inhibited, up to 127.8% as compared to the control. The low molecular peptide inhibited hyaluronidase activity as 535.7 ${\mu}g/mL$ of $IC_{50}$. It can be concluded that the relatively low molecular weight peptide, fucoidan, from A. amurensis has excellent cosmetic and immunomodulatory activities, which can be considered as a possible resource of new cosmetic agents for skin immunomodulation.

• Journal of Dairy Science and Biotechnology
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• v.14 no.2
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• pp.157-164
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• 1996

This study aimed increase the quality during ripening of Cheddar cheese made with proteinase-negative mutant of Streptococcus lactis KCTC 1913 selected by curing. The degradation of protein during cheese ripening were investigated by electrophoresis and chromatography. The results were summarized as follow ; 1. The number of lactic acid bacteria decreased with the ripening stage, and that of the control cheese decreased faster than that of the cheese made with mutant. 2. Polyacrylamide gel electrophoretic analysis of cheese caseins revealed no difference between the cheese made with mutant and the control cheese, but differences along with the ripening stage were evident. 3. On Sephadex G-25 column chromatography, the extracts of bitter components from the green cheese and 3 month ripended cheese were fractionated into 3 fractions. With the progress of ripening, bitter peptides were degraded to rather small peptides or free amino acids. 4. Sensory evaluation of the 3 month ripended Cheddar cheese found no significant differences in color but the cheese made with mutant evidenced higher palatability in flavor and better texture than the control cheese. 5. The yields of the cheddar cheese made with mutant was 0.14% higher than that of the control cheese.